Date Conversion CST in angular2

Question

I am getting time like "DOB": "/Date(862588800000+0800)/" from json API but I have to convert it into something like Date Format : 04/28/2017 10:20:05 (MM/dd/yyyy HH:mm:sss) . Need help

Answer 1

You can start by parsing the value to a Date object, then formatting the output.

The first number part appears to be a time value that is milliseconds since the epoch (1970-01-01), followed by a timezone offset in HHMM. Time values before the epoch are negative, so a regular expression to get the parts might be:

/[+-]?\d+/g

which should match both the time value and the offset.

The time value can adjusted by the offset then used to create a Date (the value passed to the Date constructor needs to be a number, or it will be parsed as if it's a string):

function parseDate(s) {
  // Get the parts
  var b = s.match(/[+-]?\d+/g);

  // If appears invalid, return invalid Date      
  if (!b || b.length != 2) return new Date(NaN);
  
  // Get sign of offset
  var sign = +b[1] < 0? -1 : 1;

  // Convert offset to milliseconds
  // Multiplication converts the strings to numbers so + adds
  var offset = sign * b[1].substr(1,2)*3.6e6 + b[1].substr(3,2)*6e4;

  // Adjust time value by offset, create a Date and return it
  // Subtraction also converts the time value to a number
  return new Date(b[0] - offset);
}

var s = '/Date(862588800000+0800)/';

console.log(parseDate(s));

The validation could also use a regular expression like:

/\(-?\d+[+-]\d{4}\)/.test(s)

As for formatting the Date, there are many questions about that already, see Where can I find documentation on formatting a date in JavaScript?